Step 1: Understanding the Concept:
Carbohydrates are classified by how many monosaccharide units they give on hydrolysis: monosaccharides (1), disaccharides (2), trisaccharides (3) and polysaccharides (many).
Step 2: Apply to maltose:
Maltose gives two molecules of glucose on hydrolysis. The two glucose units are joined by an alpha-1,4-glycosidic bond.
Step 3: Conclusion:
Maltose is a disaccharide, option B. Sucrose and lactose are other common disaccharides.
Final Answer:
Maltose is a disaccharide.
\[ \boxed{\text{(B) }\text{Disaccharide}} \]